ConstFuture
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package util
Register a FutureEventListener to be invoked when the computation completes.
Register a FutureEventListener to be invoked when the computation completes. This method is typically used by Java programs because it avoids the use of small Function objects.
Compare this method to transformedBy. The difference is that
addEventListener is used to perform a simple action when a
computation completes, such as recording data in a log-file. It
analogous to a void method in Java: it has side-effects and no
return value. transformedBy, on the other hand, is used to
transform values from one type to another, or to chain a series
of asynchronous calls and return the result. It is analogous to
methods in Java that have a return-type. Note that
transformedBy and addEventListener are not mutually
exclusive and may be profitably combined.
Sequentially compose this with f.
Delay the completion of this Future for at least
howlong from now.
Delay the completion of this Future for at least
howlong from now.
Invoked regardless of whether the computation completed successfully or unsuccessfully.
Invoked regardless of whether the computation completed successfully or unsuccessfully. Implemented in terms of respond so that subclasses control evaluation order. Returns a chained Future.
The returned Future will be satisfied when this,
the original future, is done.
the side-effect to apply when the computation completes.
If this, the original future, succeeds, run f on the result.
If this, the original future, succeeds, run f on the result.
The returned result is a Future that is satisfied when the original future
and the callback, f, are done.
If the original future fails, this one will also fail, without executing f
and preserving the failed computation of this.
Converts a Future[Future[B]] into a Future[B]
Converts a Future[Future[B]] into a Future[B]
Invoke the callback only if the Future returns successfully.
If this, the original future, results in an exceptional computation,
rescueException may convert the failure into a new result.
If this, the original future, results in an exceptional computation,
rescueException may convert the failure into a new result.
The returned result is a Future that is satisfied when the original
future and the callback, rescueException, are done.
This is the equivalent of map for failed computations.
Makes a derivative Future which will be satisfied with the result of the parent.
Makes a derivative Future which will be satisfied with the result of the parent. However, if it's interrupted, it will detach from the parent Future, satisfy itself with the exception raised to it, and won't propagate the interruption back to the parent Future.
This is useful for when a Future is shared between many contexts, where it may not be useful to discard the underlying computation if just one context is no longer interested in the result. In particular, this is different from Future#masked in that it will prevent memory leaks if the parent Future will never be satisfied, because closures that are attached to this derivative Future will not be held onto by the killer Future.
Is the result of the Future available yet?
Is the result of the Future available yet?
Checks whether a Unit-typed Future is done.
Checks whether a Unit-typed Future is done. By convention, futures of type Future[Unit] are used for signalling.
Is this Awaitable ready? In other words: would calling Awaitable.ready block?
Is this Awaitable ready? In other words: would calling Awaitable.ready block?
Combines two Futures into one Future of the Tuple of the two results.
Combines two Futures into one Future of the Tuple of the two results.
Returns the result of the computation as a Future[Try[A]].
Returns the result of the computation as a Future[Try[A]].
Lowers a Future[Try[T]] into a Future[T].
Lowers a Future[Try[T]] into a Future[T].
If this, the original future, succeeds, run f on the result.
If this, the original future, succeeds, run f on the result.
The returned result is a Future that is satisfied when the original future
and the callback, f, are done.
If the original future fails, this one will also fail, without executing f
and preserving the failed computation of this.
Returns an identical future except that it ignores interrupts which match a predicate
Returns an identical future except that it ignores interrupts which match a predicate
Returns an identical future that ignores all interrupts
Returns an identical future that ignores all interrupts
Invoke the function on the error, if the computation was unsuccessful.
Invoke the function on the error, if the computation was
unsuccessful. Returns a chained Future as in respond.
chained Future
if fn is a PartialFunction and the input is not defined for a given
Throwable, the resulting MatchError will propogate to the current
Monitor. This will happen if you use a construct such as
future.onFailure { case NonFatal(e) => ... } when the Throwable
is "fatal".
this should be used for side-effects.
handle and rescue to produce a new Future from the result of
the computation.
Invoke the function on the result, if the computation was successful.
A synonym for select: Choose the first Future to be satisfied.
Polls for an available result.
Polls for an available result. If the Future has been satisfied, returns Some(result), otherwise None.
Send updates from this Future to the other.
Send updates from this Future to the other.
other must not yet be satisfied at the time of the call.
After this call, nobody else should satisfy other.
Note: using proxyTo will mask interrupts to this future, and it's
the user's responsibility to set an interrupt handler on other
to raise on f. In some cases, using
com.twitter.util.Promise.become may be more appropriate.
Raise the given throwable as an interrupt.
Raise the given throwable as an interrupt. Interrupts are
one-shot and latest-interrupt wins. That is, the last interrupt
to have been raised is delivered exactly once to the Promise
responsible for making progress on the future (multiple such
promises may be involved in flatMap chains).
Raising an interrupt does not alter the externally observable state of the Future. They are used to signal to the producer of the future's value that the result is no longer desired (for whatever reason given in the passed Throwable).
Returns a new Future that will error if this Future does not return in time.
Returns a new Future that will error if this Future does not return in time.
Note: On timeout, the underlying future is interrupted.
Same as the other raiseWithin, but with an implicit timer.
Same as the other raiseWithin, but with an implicit timer. Sometimes this is more convenient.
Note: On timeout, the underlying future is interrupted.
Same as the other raiseWithin, but with an implicit timer.
Same as the other raiseWithin, but with an implicit timer. Sometimes this is more convenient.
Note: On timeout, the underlying future is interrupted.
Support for Await.ready.
Support for Await.ready. The use of the implicit permit is an
access control mechanism: only Await.ready may call this
method.
If this, the original future, results in an exceptional computation,
rescueException may convert the failure into a new result.
If this, the original future, results in an exceptional computation,
rescueException may convert the failure into a new result.
The returned result is a Future that is satisfied when the original
future and the callback, rescueException, are done.
This is the equivalent of flatMap for failed computations.
When the computation completes, invoke the given callback function.
When the computation completes, invoke the given callback function.
The returned Future will be satisfied when this,
the original future, is done.
This method is most useful for very generic code (like libraries). Otherwise, it is a best practice to use one of the alternatives (onSuccess, onFailure, etc.).
the side-effect to apply when the computation completes.
The value of the input to k will be the result of the
computation to this future.
a chained Future[A]
this should be used for side-effects.
ensure if you are not interested in the result of the computation.
transform to produce a new Future from the result of
the computation.
Support for Await.result.
Support for Await.result. The use of the implicit permit is an
access control mechanism: only Await.result may call this
method.
Choose the first Future to be satisfied.
Choose the first Future to be satisfied.
another Future
a new Future whose result is that of the first of this and other to return
Convert a Twitter Future to a Java native Future.
Convert a Twitter Future to a Java native Future. This should match the semantics of a Java Future as closely as possible to avoid issues with the way another API might use them. See:
http://download.oracle.com/javase/6/docs/api/java/util/concurrent/Future.html#cancel(boolean)
An offer for this future.
An offer for this future. The offer is activated when the future is satisfied.
When this future completes, run f on that completed result
whether or not this computation was successful.
When this future completes, run f on that completed result
whether or not this computation was successful.
The returned Future will be satisfied when this,
the original future, and f are done.
Transform the Future[A] into a Future[B] using the FutureTransformer.
Transform the Future[A] into a Future[B] using the FutureTransformer. The FutureTransformer handles both success (Return) and failure (Throw) values by implementing map/flatMap and handle/rescue. This method is typically used by Java programs because it avoids the use of small Function objects.
Compare this method to addEventListener. The difference is
that addEventListener is used to perform a simple action when
a computation completes, such as recording data in a log-file.
It analogous to a void method in Java: it has side-effects and
no return value. transformedBy, on the other hand, is used to
transform values from one type to another, or to chain a series
of asynchronous calls and return the result. It is analogous to
methods in Java that have a return-type. Note that
transformedBy and addEventListener are not mutually
exclusive and may be profitably combined.
Note: The FutureTransformer must implement either flatMap
or map and may optionally implement handle. Failing to
implement a method will result in a run-time (AbstractMethod)
error.
Convert this Future[A] to a Future[Unit] by discarding the result.
Convert this Future[A] to a Future[Unit] by discarding the result.
Convert this Future[A] to a Future[Void] by discarding the result.
Convert this Future[A] to a Future[Void] by discarding the result.
Returns a Future[Boolean] indicating whether two Futures are equivalent.
Returns a Future[Boolean] indicating whether two Futures are equivalent. Note that Future.exception(e).willEqual(Future.exception(e)) == Future.value(true).
Returns a new Future that will error if this Future does not return in time.
Returns a new Future that will error if this Future does not return in time.
Note: On timeout, the underlying future is not interrupted.
to run timeout on.
indicates how long you are willing to wait for the result to be available.
exception to throw.
Returns a new Future that will error if this Future does not return in time.
Returns a new Future that will error if this Future does not return in time.
Note: On timeout, the underlying future is not interrupted.
Same as the other within, but with an implicit timer.
Same as the other within, but with an implicit timer. Sometimes this is more convenient.
Note: On timeout, the underlying future is not interrupted.
Block, but only as long as the given timeout, for the result
of the Future to be available.
Block, but only as long as the given timeout, for the result
of the Future to be available.
(Since version 6.2.x) Use Await.result
Block indefinitely, wait for the result of the Future to be available.
Block indefinitely, wait for the result of the Future to be available.
(Since version 6.2.x) Use Await.result
(Since version 6.0.0) Provided for API compatibility; use raise() instead.
Demands that the result of the future be available within
timeout.
Demands that the result of the future be available within
timeout. The result is a Return[_] or Throw[_] depending upon
whether the computation finished in time.
(Since version 6.2.x) Use Await.result(future.liftToTry)
Alias for apply().
Alias for apply().
(Since version 6.2.x) Use Await.result
(Since version 6.2.x) Use Await.result(future.liftToTry).isReturn
(Since version 6.2.x) Use Await.result(future.liftToTry).isThrow
A Future that is already completed. These are cheap in construction compared to Promises.